To seal a rotary union effectively, several key factors should be considered. Here are some common methods and techniques used to achieve a reliable and leak-free seal in rotary unions:

Sealing Mechanisms: Rotary unions typically employ one or more sealing mechanisms to prevent fluid leakage. The choice of sealing mechanism depends on the specific application and requirements. Common sealing mechanisms include:

Mechanical Seals: These are commonly used in high-pressure or high-speed applications. Mechanical seals consist of two mating surfaces that create a dynamic seal as they rotate against each other. They often incorporate O-rings, gaskets, or other sealing elements to enhance the sealing performance.

Lip Seals: Lip seals use a flexible lip or lip seal ring that makes contact with the rotating shaft to create a barrier against fluid leakage. They are suitable for low to medium pressures and can accommodate some misalignment or shaft runout.

O-Rings: O-rings are circular elastomeric seals that are placed in grooves to create a static or dynamic seal between two mating surfaces. They are widely used in rotary unions due to their versatility and effectiveness in sealing fluids.

Brush Seals: Brush seals consist of bristles made of flexible materials such as nylon or metal. They form a barrier against fluid leakage by creating a tight contact with the rotating shaft. Brush seals are suitable for high-speed applications and can handle some misalignment.

Quality Materials: Selecting appropriate materials is crucial for achieving effective sealing in rotary unions. The materials used should be compatible with the fluids being transferred, as well as the operating conditions, including pressure, temperature, and rotational speed. The sealing components should have good chemical resistance, wear resistance, and dimensional stability to ensure long-term sealing performance.

Surface Finish: The surface finish of the rotating and stationary components that come into contact with the sealing elements is important for achieving a proper seal. Smooth and polished surfaces help reduce friction and wear, ensuring better sealing performance. The surfaces should be free from imperfections, nicks, or scratches that could compromise the seal.

Lubrication: Proper lubrication is essential to reduce friction and wear between the sealing components, ensuring smooth operation and extending the life of the rotary union. Lubricants should be compatible with the sealing materials and the fluids being transferred. It is important to follow the manufacturer's recommendations regarding lubrication frequency and type.

Maintenance and Inspection: Regular maintenance and inspection of the rotary union are crucial to identify any wear, damage, or deterioration of the sealing components. This allows for timely replacement or repair to prevent potential leaks. Following the manufacturer's guidelines for maintenance intervals and procedures is recommended.

Proper Installation: Correct installation of the rotary union is vital for ensuring effective sealing. This includes proper alignment of the union with the piping or equipment, correct torque application for fasteners, and appropriate connection of fluid lines. Improper installation can lead to misalignment, excessive stress on the sealing components, and potential leaks.

It is important to let us know the specific to the rotary union being used, as different designs and applications then we can make a suitable design for you.